The antiaging effect of edible bird's nest on the skin of healthy women: a randomized controlled trial

Skin is an important barrier organ of the human body. As we age, the appearance and function of our skin deteriorate, which poses health risks. The use of edible bird's nest (EBN) to nourish the skin is an ancient method in Asia. However, the role and mechanism of EBN products in improving human skin aging are still unclear. Therefore, we conducted a randomized controlled trial that included 92 healthy female volunteers aged 25–45 years. They were randomly divided into the high-dose group, the low-dose group, and the control group, and they completed a 12-week treatment. The results showed that the consumption of high-dose EBN significantly improved skin moisture and elasticity by 22.14% and 5.89%, respectively, and significantly reduced the number of deep wrinkles, light wrinkles and spot area by 18.47%, 0.64%, and 3.05%, respectively. ELISA results showed that EBN decreased the expression of inflammatory factors (IL-6 and TNF-α) and serum factors (NO, MMP-1, MMP-9). Moreover, EBN can reverse the aging-induced decreases in SOD and LOX, thus slowing down the aging process. Fecal metagenome results showed that EBN significantly increased the abundance of beneficial bacteria (<em>Bacteroides_uniformis</em> and <em>Bacteroides_finegoldii</em>). Serum and fecal non-target metabolomic results showed that EBN significantly increased serum and fecal metabolite (N-methylnicotinamide, 2-deoxyribose 5-phosphate, and dimethylmalonic acid) concentrations compared with the control group. Furthermore, correlation analysis revealed a positive association between N-methylnicotinamide levels and skin elasticity. These findings suggest that EBN may ameliorate skin aging by enhancing the diversity of beneficial gut bacteria and their metabolites.